The present invention relates to the treatment of stress urinary incontinence xe2x80x9cSUI,xe2x80x9d and, in particular, to improved methods and surgical devices for the surgical treatment of SUI in females. The devices disclosed herein are additionally useful in a wide variety of other surgical procedures.
Genuine stress incontinence is the involuntary loss of urine due to a sudden rise in intra-abdominal pressure. It has been estimated that between 40% and 50% of young, healthy nulliparous women admit to occasional mild stress incontinence; however, at least 80% of stress incontinence patients are in the perimenopausal age group and are multiparous. Raz3 has suggested that the female urethral continence mechanism is dependent on the interaction of four urethral factor: urethral closing pressure, urethral length, urethrotrigonal anatomy, and urethral reception of intra-abdominal pressure.
The urethral closing pressure is predominantly a result of the interaction of smooth and striated muscle sphincter activity, but there is also some contribution by nonmuscular urethral factors such as the submucosal vascular plexus, the elastin and collagen content of the urethral tissues, and a sphincter like effect of the mucosa. There has been considerable diversity of opinion regarding the anatomic structure and the innervation of the urethral sphincters, and a variety of views have been expressed in the literature.
Lapides and associates have stressed the importance of urethral length in the maintenance of continence in the female. However, although it certainly interacts with other factors to contribute to continence, a short urethra alone will not produce incontinence. Urethral length varies considerably in normal women, and women with proven genuine stress urinary incontinence do not invariably have urethral shortening.
Urethrotrigonal anatomy, which can be demonstrated by lateral cystourethrography, should fulfill certain criteria. The bladder base should lie above the level of the inferior ramus of the symphysis, and with straining should not descend more than 1.5 cm. There should be a normal urethrotrigonal alignment with an angle normally less than 100 degrees, and the urethral axis should be approximately 35 degrees from the vertical. In the hypermobile situation loss of all of the normal anatomic features may occur, a radiologic finding that correlates with the clinical finding of cystourethrocele. However, clinical experience has shown that the coexistence of cystourethrocele and incontinence does not predict that the incontinence is of a genuine stress variety.
The transmission of intra-abdominal pressure to the intra-abdominal portion of the proximal urethra is also reported to be important in the maintenance of continence. This is a passive phenomenon, and is the result of the normal anatomic configuration just described. Whenever there is a rise in intra-abdominal pressure during such stresses as coughing or straining, the pressure is transmitted not only to the bladder but also to the proximal urethra, with resultant increase in the closing pressure, and prevention of leakage. If the urethral axis is altered, rotational descent will drop the proximal urethra and bladder base from its intra-abdominal location, and will obviously impair such pressure transmission.
A wide variety of operations have been used to correct this condition, generally involving the principles of elevating the bladder neck anteriorly and/or elongating and narrowing the proximal urethra. Two of the most popular operations today for female stress incontinence are the Marshall-Marchetti-Krantz and Birch vesicourethropexies. The Marshall-Marchetti-Krantz technique has at least an eighty-five percent success rate, against which other operative success rates must be measured. Recently, the Pereyra operation and its modifications have enjoyed some popularity, but less than basic techniques.
Notwithstanding the foregoing, however, there remains a need for an improved treatment for SUI. Preferably, the treatment is as noninvasive as possible under the circumstances, and will eliminate or minimize hospitalization and the use of general anesthetics. In addition, there remains a need for improved medical instrumentation such as drill guides and suture passers for use in connection with SUI treatment and other medical procedures.
There is provided in accordance with one aspect of the present invention a drill guide for directing a drill bit at a selected site on a bone. The drill guide comprises a housing, and at least two chambers extending axially within the housing. Each of the chambers has an opening at the distal end. A plunger is provided in each of the chambers, each plunger axially movable from a first retracted position to a second extended position. A probe is mounted on the distal end of each of the plungers, and adapted for retraction within the open end of the chamber and extension outside of the open end of the chamber. In a simplified embodiment, each of two or more probes is axially movably disposed within the housing, without the use of a distinct plunger. A drill guide channel extends axially through the housing, within a plane parallel to the plane joining the axes of the first and second chambers, and in between the axes of the first and second chambers.
Preferably, one or both of the plungers is provided with a releasable lock for releasably retaining the plunger in the retracted position, thereby minimizing the likelihood of accidental needle sticks. The preferred probe comprises a hypodermic needle or a sharpened solid wire. In a two probe embodiment, the axes of the first and second probes are separated by a distance within the range from about 5 mm to about 15 mm. Preferably, the axis of the drill guide channel is approximately equidistant from the axes of each of the probes.
In accordance with another aspect of the present invention, there is provided an alternate embodiment of a drill guide for use in locating drill sites in a patient""s body. The drill guide comprises a body, a handle connected thereto, and one or more bores extending through said body. Each bore has an opening at a distal end. A probe is provided in each bore, the probe being axially movable from a retracted to an extended position. A drill guide bore, which may also act as one of the probe bores, extends axially through the body. A suture slot extends from outside of the body to the drill guide bore along the length of the body. Serrations are provided on the distal end of the body, aiding in maintaining the opening of a drilled hole. In a two probe embodiment, the axes of the probes are separated by a distance of about 5 to 10 mm. Preferably, the probes of this embodiment are a unitary element, such as a wire or needle. Further, it is desired that the drill guide bore and any probe bores lie in a line perpendicular to the longitudinal axis of the body.
In accordance with the further aspect of the present invention, there is provided a method of positioning a drill guide over a drilling site on bone, comprising the steps of providing a drill guide of the type having a housing, at least two axially extendable probes within the housing, and a drill guide extending through the housing. A first probe is extended from the retracted position to the extended position, and advanced through the tissue until it contacts a bone. The second probe is thereafter extended from the retracted position to the extended position, until the second probe contacts the bone. If the first extension of the second probe does not result in a contact, both probes are retracted within the housing, and the drill guide is translated along the sagittal or other axis. The first probe is thereafter reextended and the foregoing steps are repeated until both the first and second probes contact the bone.
In accordance with another aspect of the present invention, there is provided a method of installing a bone anchor in a bone, utilizing the drill guide defined above. In accordance with the installation method, each of the probes is sequentially extended and advanced through tissue as described until each of said probes is in contact with the bone. A drill bit is thereafter advanced through the drill guide channel and a hole is drilled in the bone. The drill bit is thereafter withdrawn from the drill guide channel, and a suture anchor is advanced through the drill guide shaft and into the bone.
In accordance with another aspect of the present invention, there is provided a suture passer of the type adapted for releasably retaining a suture. The suture passer comprises a handle, and an elongate tubular probe guide extending in a distal direction straight or curved from the handle. An elongate probe is axially movably disposed within the tubular probe guide, for motion between a first retracted position and a second extended position in which the sharpened distal tip of the probe is exposed. An annular recess is provided on the probe, to cooperate with an opening on the tubular guide for receiving a suture. The probe is axially movable with respect to the probe guide between a first position in which the annular recess is aligned with the opening for receiving a suture therein, a second position wherein the annular recess is out of alignment with the opening, to trap or retain a suture therein and a third position in which the distal probe tip is exposed.
In accordance with another aspect of the present invention, there is provided a drape and exposure system comprising a vaginal drape, speculum and buttock plate for isolating the surgical field, providing a mounting surface for surgical instruments, and opening the surgical area for access. The vaginal drape comprises a large section of flexible, sterilizable material. Preferably, the drape has a large abdominal drape connected to a moisture barrier. The drape has a transparent surgical window with an adhesive backing for viewing the surgical area. Alternatively, the window may be an opening through the drape devoid of material. An opening is provided below the window to allow a gloved hand access through the drape to aid in placement of the drape. A vaginal flap or stretchable moisture-proof fabric is provided in the drape to allow a speculum to be placed therein.
Adhesive strips or velcro ties spaced around the window provide a means to attach cables or tubes used for other ancillary surgical equipment. Further, a plate pocket is provided in the moisture barrier for placement of the buttock plate.
The buttock plate is a mainly flat support surface. A mounting arm is provided in one end of the plate, extending upwards about 50 mm and being about 50 mm in width. A bore is provided in the mounting arm to accept a threaded knob for securing various tools to the plate.
The speculum is a member having a support stem with a slot therein to allow mounting to the plate, and a concave engaging member attached to the top of the stem. The concave member is an arcuate shaped member for placement in the vagina. Preferably, the concave member is inserted into the vaginal flap of the drape and then extended into the vagina to aid in isolating the surgical field.
In accordance with yet another aspect of the present invention, there is provided a suture support for providing a structure to which sutures may be anchored inside the body so as to reduce trauma to body tissue. In one form, the suture support comprises a circular plate about 15 mm in diameter and less than about 1 mm in thickness, having a small tab mounted on one side thereof for attachment of a suture. In another form, the support comprises a lattice constructed from wire having a diameter of about 1 mm. In another embodiment the support comprises a hub area with spokes radiating outwardly thereto.
In accordance with another aspect of the present invention there is provided a tissue staple and staple applier for use in suspending tissue in transvaginal bladder suspension procedures.
The tissue staples are arcuate elliptical structures preferably made of spring wire. Sharpened ends are provided on the staple for penetration of tissue. The body of the staple is located in between the ends and may have an enlarged center section in order to aid in distribution of forces on the tissue, and it may have openings to allow ingrowth of tissue.
The staple applier comprises a scissor like body provided with two arms having handles at one end, and a pair of pressing support members at the other end. The arms are about 160 mm long and are rotatably attached to one another by a pin located at the end of the arms opposite the handles.
The pressing members extend upwards from the pinned ends of the arms, mounted generally perpendicular to the longitudinal axis of the applier. The pressing members are arcuate in shape, their inside surface shape mirroring the shape of the staples, and their free tips being sharp to allow tissue penetration. The pressing members are designed such that when the arms of the applier are open, the members are a distance away from one another to allow the introduction of a staple therebetween. When the arms of the applier are pressed together, the members move towards one another to press the sharp ends of the staple closed.
An opposing pair of staple removal prongs are mounted to, and between, the pressing members. The prongs are generally U-shaped shafts extending from the members outwardly and then back in between the members perpendicular to the axis of the applier. The prongs may be advanced towards one another or drawn apart from each other by the movement of the arms.
There is a xe2x80x9cCxe2x80x9d clamp provided in accordance with another aspect of the present invention. The xe2x80x9cCxe2x80x9d clamp is an alternative to the drill guide and is designed for use with the buttock plate. The xe2x80x9cCxe2x80x9d clamp aids in locating a drill bit through the pubic region.
The xe2x80x9cCxe2x80x9d clamp comprises a support arm, attachment member, and guide arm. The attachment member is a plate having a slot therein to allow passage of a knob therethrough for securing the clamp to the buttock plate. The support arm is a primarily L shaped member extending from the attachment member to a distal end where a drill stop is located. The support arm is shaped so that when used in a bladder neck suspension procedure, in use, it extends from the attachment member located outside the body to its distal end located in the vagina. A bore is provided in the support arm near its connection with the attachment member for acceptance of the guide arm.
The guide arm is shaped like an inverted L, having a shaft-like stem which engages the support arm through the bore. The shaft is threaded and may be locked in relation to the support arm by knobs. The drill guide portion of the guide is a wide block. A drill guide bore and one or more probe bores are located in the drill guide. Probes are provided for engaging the probe bores. The probes and bores are similar to those described in the drill guide. The drill guide bore is oriented such that a line passing along its axis encounters the drill step on the support arm.
In accordance with another aspect of the present invention, there is provided a surgical bladder neck suspension procedure involving use of the tissue staples and drape and exposure system. This method is accomplished entirely transvaginally through a tissue suspension procedure. In accordance with this procedure, the patient is first placed in the lithotomy position and sterily prepared. The vaginal drape is positioned over the abdomen and secured thereto. The buttock plate is inserted into the buttock plate pocket, which lies under the patient and with the guide arm extending upwards between the legs. The speculum is inserted into the vaginal flap and inserted into the vagina. The speculum is secured to the arm of the buttock plate.
A staple is loaded into the applier with the arms of the applier in the open position. The pivot end of the applier is inserted into the vagina. Once aligned to one side of the bladder neck, the staple and support members are pressed into the vaginal mucosa and upwards into the iliopectineal or other ligament. The arms of the applier are pressed together to close the staple. The applier may then be removed and the process repeated in the other side of the bladder neck.
In accordance with another aspect of the present invention, there is provided a bladder neck suspension procedure involving use of the suture supports, anchors, and the xe2x80x9cCxe2x80x9d clamp or drill guide or suture passer.
In accordance with this procedure, the drape and exposure system are prepared on the patient as before. The suture passer is passed through an incision made over the pubic bone into the vagina. A suture that is attached to a suture support is captured in the suture channel of the passer at the other. The passer is passed back out of the patient, until the suture is pulled slightly taut. The free end of the suture is then affixed to the pubic bone with a knot, plug, or anchor. The anchor may be placed by pressing it into a hole drilled into the bone, as located by the xe2x80x9cCxe2x80x9d clamp or drill guide.
Alternatively, the drill guide or xe2x80x9cCxe2x80x9d clamp may be used to position a drill bit for drilling a passageway from the pubic area to the vagina. The free end of the suture is then passed through the drilled hole up from the vagina to the pubic area. The free end of the suture may then be tied off or affixed by a plug or anchor to prevent it from pulling back through.
In accordance with a further aspect of the present invention, there is provided a surgical bladder neck suspension procedure, for the treatment of stress urinary incontinence. In accordance with the method, a technique of creating a suspension web comprising a plurality of lengths of suture is constructed extending between the pubocervical fascia and the pubic bone, on each of the right and left sides of the midline. Sutures are carried through tissue utilizing the suture passer disclosed herein, and sutures are tied down to the pubic bone utilizing a bone anchor positioned on each of the right and left sides of the midline by a drill guide as disclosed herein. Prior to tying, sutures are appropriately tensioned by advancing the suture around the suture tensioner disclosed herein and tying in a conventional manner. Thereafter, the suture tensioner is removed and the surgical site prepared and closed in a conventional manner.
These and additional features and advantages of the present invention will become apparent from the detailed description of preferred embodiments which follows, when taken together with the attached drawings and claims.